søndag den 30. september 2018

Morsetrainer with BBC micro:bit

My grandchild Noah showed me his new BBC micro:bit. It is a tiny microcomputer which is being distributed free to school children aged 10-11 years. The purpose is to introduce the pupils to coding. The micro:bit computer is small, about half size of a credit card.

The tiny micro:bit computer (rear view).
I decided to create "something" for pupils in relation to ham radio. I ended up with a morsetrainer. It shows characters (letters, numbers) on the microbit display and plays them loud in morse code, one letter at a time. The pupil decides the pace of new letters coming via button pressure. Another button press repeats the letter.

Micro:bit displays "A" (front view).
The morsetrainer's circuit diagram is shown below. The speakerboard is an accessory. A pair of computer speakers can do the same. The different units are connected using short cables with crocodile-clips.
Circuit diagram of the morsetrainer.
Sending morse code requires a morse key. My idea was to build one, rather than buying one. Building a morse key can be exciting for pupils. They produce something useful with their own hands! The key shown below is made from wood, a plastic ruler, a knob, and some screws, bolts, and wires.

Homemade morse key.
If you want to download the Python source code and the hexfile, download this ZIP-file.
If you want to view a video (in Danish), click this link.
If you want to download a PDF description (in Danish), go to this page.

73 from OZ1BXM Lars Petersen